Injections of imaging contrast material during dialysis related procedures is usually performed manually using a standard syringe, with evidence suggesting optimal results have correlation with ease of injection (especially, injection force applied by the physician) and amount of imaging contrast material injected within a short period of time. Based on such evidences, current techniques are based on using standard angiographic infusion catheters for peripheral and arteriovenous (AV) access that have a single infusion opening located at the catheter distal tip, which commonly provide high quality angiographic and imaging results. Recently, there has been motivation to develop infusion balloon catheters with a single side hole, or with a plurality of side holes, provided proximally to the balloon member of the catheter. The main justification for that is to allow localized low-dose injection of imaging contrast material (usually, in the same direction as blood flow) against the proximal periphery of the inflated and expanded balloon member of the infusion catheter.
Currently know forms of side hole infusion balloon catheters, employed using standard injection parameters, may be considered prone to produce jets generally directed toward blood vessel walls. Production of such jets, instead of streamlined injection, of imaging contrast material within the blood flow can lead to undesirable and disadvantageous effects such as of creating local turbulence, which results in immediate dilution of imaging contrast material within the blood. Such result is accompanied by decreasing imaging contrast quality, instead of locally replacing blood with contrast material that provides high density of local imaging contrast material. Another disadvantage of having jet producing side openings in infusion balloon catheters may be the inherent risk in potentially damaging blood vessels, especially, small blood vessels. Multiple or/and narrow jets aimed at blood vessel walls may cause perforation or dissection of wall tissue, especially, in blood vessels damaged either by disease or by recent intervention or manipulation.
Another difficulty that may arise during catheter infusions is the resistance to flow of infusion material, such as of imaging contrast material. The small cross-sectional area, long travel through the infusion lumen, together with, at times, insufficient mechanical advantage produced by the injecting apparatus (syringe prefilled with the contrast media), affects such resistance to flow.
In view of at least the preceding disadvantages and limitations associated with currently known and used infusion balloon catheters, there is an on-going need for developing and implementing new and improved infusion balloon catheters, along with corresponding methods of manufacturing such catheters.